1. Field of the Invention
This invention relates to pattern recognition devices for recognizing line patterns, and particularly to a line recognition method of recognizing a line pattern consisting of dash lines or chain lines used for specifying different kinds of patterns, i.e., to the recognition of a segmented line form as a single, connected line, not as separate line segments.
2. Descrption of the Prior Art
In various design drawings, the difference between lines is illustrated by changing the kinds of lines used, such as a solid line, a dash line, chain line and the like. Thus, to recognize this design drawing, it is necessary to recognize the dash line, the chain line and the like as a single, connected line. Also, to know the difference between these lines, it is necessary to recognize the form of the line and the path thereof.
There has been used a digitizer or the like for reading a drawing and inputting data to a computer, in which the reading indicator for the coordinates is manually moved to feature points such as end points and inflection or bending points of lines which represent characteristics of the lines so that the read coordinates are stored in the computer. In this case, the identification of the lines is also manually input to the computer by another means. The discrimination of lines in accordance with this conventional method is performed by the human pattern recognition ability and this fact definitely prevents the digitizing operations from being fully automated.